This application claims the priority of German patent 297 21 042.4, filed Nov. 28, 1997, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a weaving loom, particularly an air nozzle weaving loom, having a reed strip which carries a weaving reed and which, for the purpose of picking and looping weft yarns to the beating up edge of a weft, carries out uniform swinging motions from a picking position into a beating up position and in the reverse direction about a longitudinal axis of a driving or reed shaft, having a first nozzle arrangement which consists of several main nozzles having a blow pipe, the main nozzles being accommodated in a main nozzle block according to an order system, and the main nozzle block being connected with the reed strip carrying out the swinging motions, and having a second stationary nozzle arrangement which is situated in front of the first nozzle arrangement in the weft direction and consists of several prenozzles with a blow pipe, the yarn guiding duct of each blow pipe of the respective prenozzle, at the point in time of the picking of the weft yarn, being situated, aligned with the yarn guiding duct of the blow pipe, opposite the respective main nozzle.
For the picking of the woof yarn, known air nozzle weaving looms have a main nozzle block with several main nozzles with a blow pipe of a defined length which are accommodated according to a defined order system and can be acted upon pneumatically, the respective blow pipe aiming at the weft picking duct of a weaving reed. The main nozzle block is arranged on the reed strip of the weaving loom carrying the weaving reed, specifically such that the main nozzle block can be adjusted relative to the weaving reed.
For implementing a high woof picking performance, it is known to assign to each main nozzle integrated in the main nozzle block a separately arranged prenozzle which, viewed in the picking direction of the weft yarn, is positioned at a distance in front of the respective main nozzle.
The respective prenozzle has a blow pipe of a defined length which is aligned in the direction of the respective main nozzle such that weft yarn deflections, which damage the weft yarn, are largely avoided.
In this case, the alignment of the respective prenozzle with the concerned main nozzle is time-consuming, specifically if a large number of prenozzles must be aligned with a corresponding large number of main nozzles.
In view of this background, it is an object of the invention to provide a prenozzle arrangement which eliminates the need for individual alignment of each prenozzle with the pertaining main nozzle and which avoids weft yarn deflections between the prenozzles and the main nozzles during the weft yarn picking.
According to the invention, this object is achieved in that the individual prenozzles with the blow pipe are accommodated in a prenozzle block according to an order system (geometric configuration) which corresponds to the order system (geometric configuration) of the main nozzles in the main nozzle block, which order system has the result that, with the alignment of a single prenozzle with the corresponding main nozzle, all other prenozzles during the picking of the weft yarn are aligned with the corresponding main nozzles, specifically also if the prenozzle block is mounted on a stationary carrier which is independent of the reed stay.
These objects have also been achieved according to the present invention by providing an air nozzle weaving loom, having a reed stay which carries a weaving reed and which uniformly swings between a picking position and a beating up position about a longitudinal axis of a driving shaft in order to pick and beat up weft yarns, having a first nozzle arrangement including a plurality of main nozzles having respective main nozzle blow pipes, the main nozzles being positioned in a main nozzle block in a given geometric configuration, and the main nozzle block being fixedly connected with the reed stay, and having a second stationary nozzle arrangement which is situated in front of the first nozzle arrangement in a weft direction and includes a plurality of prenozzles with respective prenozzle blow pipes, a yarn guiding duct of each of said prenozzle blow pipe being aligned in a weft yarn picking position with a respective yarn guiding duct of the main nozzle blow pipe, opposite the respective main nozzle, wherein the prenozzles with the prenozzle blow pipes are positioned in a prenozzle block in a geometric configuration which corresponds to said given geometric configuration of the main nozzles, the prenozzle block being connected with a weaving loom carrier, wherein an alignment of the yarn guiding duct of a single one of said prenozzles with the yarn guiding duct of a corresponding one of the main nozzles effects an alignment of all of the yarn guiding ducts of the prenozzles with the corresponding main nozzles.
These objects have also been achieved according to the present invention by providing an arrangement of main nozzles and prenozzles in an air weaving loom, comprising: a main nozzle block including a plurality of main nozzles extending there through in a weft direction, said plurality of main nozzles being arranged in a given geometric configuration with respect to a longitudinal center axis of said main nozzle block; a prenozzle block arranged upstream of said main nozzle block with respect to said weft direction, said prenozzle block including a plurality of prenozzles extending therethrough in said weft direction, said plurality of prenozzles being arranged in a geometric configuration with respect to a longitudinal center axis of said prenozzle block which corresponds to said given geometric configuration of said main nozzles.
These objects have also been achieved according to the present invention by providing a prenozzle arrangement for an air weaving loom having a main nozzle block including a plurality of main nozzles extending therethrough in a weft direction, said plurality of main nozzles being arranged in a given geometric configuration with respect to a longitudinal center axis of said main nozzle block, said prenozzle arrangement comprising: a prenozzle block to be arranged upstream of said main nozzle block with respect to said weft direction, said prenozzle block including a plurality of prenozzles extending therethrough in said weft direction, said plurality of prenozzles being arranged in a geometric configuration with respect to a longitudinal center axis of said prenozzle block which corresponds to said given geometric configuration of said main nozzles.
These objects have also been achieved according to the present invention by providing a method of making a prenozzle for an air weaving loom having a main nozzle block including a plurality of main nozzles extending therethrough in a weft direction, said plurality of main nozzles being arranged in a given geometric configuration with respect to a longitudinal center axis of said main nozzle block, said method comprising: providing a prenozzle block having a longitudinal center axis; and arranging a plurality of prenozzles in said prenozzle block in a geometric configuration with respect to said longitudinal center axis which corresponds to said given geometric configuration of the main nozzles.
In a further development of the invention, in the case of a corresponding order system, the prenozzle block can be arranged on the carrier stationarily connected with the weaving loom, the prenozzle block being rotatable about its longitudinal center axis.
A defined order system of the prenozzles and the main nozzles exists, for example, if the center axes of the nozzles are arranged symmetrically about the longitudinal center axis of the nozzle blocks on a circular path.
In such a case, by the rotation of the prenozzle block about its longitudinal center axis, each prenozzle can be assigned to an arbitrary or selected one of the main nozzles. Such an approach can be significant when weft yarns of different qualities are to be made into a woven fabric, and, for example, a weft yarn requires a prenozzle which deviates in its construction from the main nozzle. The corresponding prenozzle can then be assigned to the respective main nozzle within a short time period.
Thus, it is important with respect to the invention that, with the alignment of a single prenozzle with the corresponding main nozzle, all other prenozzles are necessarily aligned with their assigned main nozzles.
The solution according to the invention advantageously eliminates the separate alignment of the large number of prenozzles with the corresponding main nozzles, and weft yarn deflections between the prenozzle arrangement and the main nozzle arrangement which damage the weft yarn during the picking of the woof yarn are eliminated.